package com.zw.gulimall.product.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.zw.gulimall.product.dao.CategoryDao;
import com.zw.gulimall.product.entity.CategoryEntity;
import com.zw.gulimall.product.service.CategoryService;
import com.zw.gulimall.utils.PageUtils;
import com.zw.gulimall.utils.Query;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {
//    @Autowired
//    private CategoryDao categoryDao;
    @Autowired
    StringRedisTemplate redisTemplate;
    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
//        1.加入缓存，缓存的是json字符串
        String catalogJSON = redisTemplate.opsForValue().get("catalogJSON");
        if (StringUtils.hasText(catalogJSON)){
            //2.如果数据库没有查询数据库
            List<CategoryEntity> categoryEntities = listWithTreeFromDb();
            //3.将查出的数据放入缓存
            String s = JSON.toJSONString(categoryEntities);
            redisTemplate.opsForValue().set("catalogJSON",s);
            return  categoryEntities;
        }
        List<CategoryEntity> categoryEntities = JSON.parseObject(catalogJSON, new TypeReference<List<CategoryEntity>>() {
        });
        return  categoryEntities;
    }

    /**
     * 从数据库查询三级分类的数据
     * @return
     */
    @Override
    public List<CategoryEntity> listWithTreeFromDb() {
        //1、查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);

        //2、组装成父子的树形结构

        //2.1）、找到所有的一级分类
        List<CategoryEntity> level1Menus = entities.stream().filter(categoryEntity ->
                categoryEntity.getParentCid() == 0
        ).map((menu)->{
            menu.setChildren(getChildren(menu,entities));
            return menu;
        }).sorted((menu1,menu2)->{
            return (menu1.getSort()==null?0:menu1.getSort()) - (menu2.getSort()==null?0:menu2.getSort());
        }).collect(Collectors.toList());


        return level1Menus;
    }

    //递归查找所有菜单的子菜单
    private List<CategoryEntity> getChildren(CategoryEntity root,List<CategoryEntity> all){

        List<CategoryEntity> children = all.stream().filter(categoryEntity -> {
            return categoryEntity.getParentCid() == root.getCatId();
        }).map(categoryEntity -> {
            //1、找到子菜单
            categoryEntity.setChildren(getChildren(categoryEntity,all));
            return categoryEntity;
        }).sorted((menu1,menu2)->{
            //2、菜单的排序
            return (menu1.getSort()==null?0:menu1.getSort()) - (menu2.getSort()==null?0:menu2.getSort());
//            if (menu1.getSort() == null){
//                System.out.println(menu1);
//            }
//            if (menu2.getSort() == null){
//                System.out.println(menu2);
//
//            }
//            return menu1.getSort()-menu2.getSort();
        }).collect(Collectors.toList());

        return children;
    }


    @Override
    public void removeMenuByIds(List<Long> asList) {
    //todo 检查当前删除的菜单，是否被别的地方引用
        baseMapper.deleteBatchIds(asList);
    }

    //[2,25,225]
    @Override
    public Long[] findCatelogPath(Long catelogId) {
        List<Long> paths = new ArrayList<>();
        List<Long> parentPath = findParentPath(catelogId, paths);

        Collections.reverse(parentPath);


        return parentPath.toArray(new Long[parentPath.size()]);
    }

    //225,25,2
    private List<Long> findParentPath(Long catelogId,List<Long> paths){
        //1、收集当前节点id
        paths.add(catelogId);
        CategoryEntity byId = this.getById(catelogId);
        if(byId.getParentCid()!=0){
            findParentPath(byId.getParentCid(),paths);
        }
        return paths;

    }
}